Loading...
Thesis
Browse
57 results
Search Results
ThesisItem Restricted Effect of rice residue biochar on the bioavailability of lead and cadmium to Indian mustard (Brassica juncea (L.) Czern.)(Punjab Agricultural University, Ludhiana, 2020) Dubey, Shikha; Sikka, R.The investigation titled “Effect of rice residue biochar on the bioavailability of lead and cadmium to Indian mustard (Brassica juncea (L.) Czern.)” was conducted at screen house, Department of Soil Science, Punjab Agricultural University, Ludhiana during rabi season of 2018-2019. The objectives of study were to determine the effects of addition of rice residue biochar on immobilization of Cd and Pb in soil and their translocation to Indian mustard (Brassica juncea (L.) Czern.). Two differently irrigated - tube well water irrigated (TWI) and sewage water irrigated (SWI) - soils were collected and amended with four levels of rice residue biochar and further spiked with four levels of Cd and Pb individually. Spiking of Cd and Pb significantly decreased the shoot dry matter yield (DMY) in both TWI and SWI soil. The DMY in TWI soil increased by 12.5 and 19.6 per cent compared to control in Cd and Pb contaminated soil, respectively at 2 per cent addition of biochar whereas in case of SWI soil the corresponding increase was 19.2 and 17.5 per cent, respectively. Addition of rice residue biochar significantly increased the immobilization of DTPA-extractable Cd and Pb in both TWI and SWI soil. The DTPA-Cd and Pb decreased by 44.9 and 47.1 per cent in TWI soil at 4 per cent addition of biochar whereas in SWI soil the decrease was 38.1 and 39.5 per cent, respectively. Biochar addition countered the Cd and Pb content and increased the macro and micronutrient content of Indian mustard. The study indicated that rice residue biochar has potential for ameliorating heavy metal contaminated soils.ThesisItem Restricted Assessment of soil chemical and biological properties under cotton-wheat and rice-wheat cropping system in south-west part of Bathinda, Punjab(Punjab Agricultural University, Ludhiana, 2019) Kahlon, Pawandeep; Yadav, B.K.The present study was undertaken to assess different soil chemical and biological properties under cotton-wheat and rice-wheat cropping system in Sangat block of Bathinda district, Punjab. The soil samples were collected from surface soil (0-15cm) and sub-surface soil (15-30cm) using GPS location. The pH values of soils from both the cropping system was neutral to alkaline in reaction ranging higher under cotton-wheat cropping system. EC was observed to be highest in rice-wheat cropping system at both surfaces. Results revealed that organic carbon, available N, available P and available S was higher under rice-wheat cropping system. Among exchangeable bases exchangeable K was reported to be higher under cotton-wheat cropping system whereas exchangeable Ca and Na were higher under rice-wheat cropping system. DTPA-extractable micronutrients (Fe, Cu, Zn, and Mn) were higher under cotton-wheat cropping system but at par with rice-wheat cropping system. Among biological properties, higher DHA was reported in cotton-wheat cropping system whereas alkaline and acid phosphatase was reported to be higher in rice-wheat cropping system. Nutrient index value among both the cropping system was calculated and it was reported that the soil was low in N (1.4 and 1.3), Fe (1.2 and 1.1) and Ca (1.2 and 1.3), medium in K (2 and 2) and Mn (1.9 and 1.7) and higher in P (2.6 and 2), S (2.6 and 2.4), Zn (2.9 and 2.7) and Cu (3 and 2.9) availability under cotton-wheat cropping system at 0-15 and 15-30 cm depth respectively. Under rice-wheat cropping system the soil was low in Ca (1.4 and 1.5), Fe (1.4 and 1.3) and Mn (1.3 and 1.3) availability at 0-15 and 15-30 cm respectively, medium in N availability (1.6) at 0-15 cm and low (1.2) at 15-30 cm depth and medium in K (2.2 and 1.8) availability at 0-15 and 15-30 cm respectively and higher in P (2.9 and 2.7), S (2.6 and 2.6), Cu (2.8 and 2.8) and Zn (2.6) availability at 0-15 cm depth whereas Zn availability was medium (2.4) at 15-30 cm depth.ThesisItem Restricted Influence of land use systems and seasons on soil biochemical properties under rainfed conditions in sub montane Punjab(Punjab Agricultural University, Ludhiana, 2019) Arora, Raavi; Sharma, VivekLand use changes alter the soil properties and its functioning due to changes in soil microbial functions, soil organic carbon (SOC) storage and nutrient turnover in soils. In present study, a total of 150 soil samples were collected from four rainfed land use systems (agri-horticulture, agroforestry, cultivated and barren) during three seasons (summer, rainy and winter season) at two locations viz. Garhshankar (Hoshiarpur) and Nurpur Bedi (Rupnagar) for the analysis of soil biochemical properties. The results showed that soils at both locations were loamy sand to sandy loam in texture with neutral to slightly alkaline soil reaction. The electrical conductivity (EC) ranged from 0.18 to 0.23 dS m-1 at Garhshankar and 0.19 to 0.26 dS m-1 at Nurpur Bedi. Soil organic carbon content ranged from 2.18 to 5.83 and 1.99 to 5.03 g kg-1, being highest under dek and mango based system at Garhshankar and Nurpur Bedi, respectively. The soil microbial biomass carbon (MBC) ranged from 48.1 to 170.0 and 48.4 to 147.1 μg g-1 at Garhshankar and Nurpur Bedi, respectively. Among soil enzymes, the soil dehydrogenase activity (DHA) varied from 12.1 to 37.1 and 10.8 to 33.1 μg TPF g-1 hr-1, fluorescein diacetate activity from 0.65 to 2.49 and 1.17 to 2.86 μg fluorescein g-1, acid phosphatase from 14.7 to 22.2 and 16.3 to 39.1 μg PNP g-1 hr-1, alkaline phosphatase activity from 17.1 to 44.3 and 20.0 to 35.1 μg PNP g-1 hr-1, and urease activity from 4.67 to 6.62 and 5.82 to 6.38 μg NH4-N g-1 hr-1 for land use systems at Garhshankar and Nurpur Bedi, respectively. The values of soil physicochemical and biological properties, soil microbial quotient and metabolic potential were higher under agri-horticulture and agroforestry systems and least under barren system. The labile carbon fractions and carbon management index had higher values for agri-horticulture and agroforestry systems. Majority of the soil properties had higher values during rainy season as compared to winter and summer season at both Garhshankar and Nurpur Bedi. Principal component analysis and soil quality index showed that agroforestry system followed by agri-horticulture system had higher values of soil enzymes, MBC, SOC and carbon fractions. Among soil properties, SOC, available P, DTPA-Zn, DHA, mean weight diameter and urease activity at Garhshankar and SOC, MBC, EC, total organic carbon and available K at Nurpur Bedi were the most reliable and sensitive indicators for assessing soil quality under rainfed land use system in sub montane Punjab.ThesisItem Open Access Effect of irrigation scheduling and tillage for rice residue management on productivity and water use of wheat(Punjab Agricultural University, Ludhiana, 2019) Malkit Singh; Singh, K.B.The present study was conducted with three irrigation regimes based on irrigation water/open pan evaporation (IW/PAN-E) (0.6 (I1), (I2) 0.8 and 1.0 (I3)) and four tillage treatments for paddy residue management primary tillage with mouldboard plough to a depth of 25 cm (PTF+R) followed by rotavator, primary tillage with mouldboard plough to a depth of 14 cm (PTH+R) followed by rotavator, wheat sown with happy seeder in rice stubbles (NT) and secondary tillage with two discing and cultivator (CT) before sowing wheat to observe the effect of irrigation scheduling and tillage for residue management on water use and productivity of wheat for the two years (2016-17 and 2017-18). Both the soil bulk density and mean weight diameter were significantly higher in NT over PTF+R. The saturated hydraulic conductivity was significantly higher in PTF+R by 72.5% and 81.7% as compared to NT in 0- 7.5 and 7.5-15 cm soil layers respectively. Among tillage for residue management practices, the significantly higher grain yield was observed in PTF+R by 16.3% and 18.2% as compared to NT during 2016-17 and 2017-18 respectively. Significantly higher grain yield was observed in I3 by 39.5% and 37.5% as compared to I1 during 2016-17 and 2017-18 respectively. Grain yield was significantly higher under PTF+R during 2016-17 and 2017-18. The soil water retention and soil organic carbon content were significantly higher under NT as compared to PTH+R and CT. Leaf area index was significantly higher in PTF+R (by 56.8 %) as compared CT. Root length density was significantly higher by 89% in PTF+R as compared to NT. ET losses were higher under I3 than I1. PTF+R was observed to be better with respect to improvement in soil physical properties and water use in wheat.ThesisItem Open Access Effect of zinc phasing on its distribution and fractions under continous maize-wheat cropping system(Punjab Agricultural University, Ludhiana, 2019) Sonal Kumar; Verma, GayatriThe present investigation was carried out in the pre-established experiment initiated in year 2012 (rabi season) at the Research Farm of Department of Soil Science, Punjab Agricultural University, Ludhiana in randomized block design with thirteen treatments replicated three times. The soil of the experimental area was sandy loam in texture and neutral in soil reaction. Surface (0.0-0.15 m) and sub-surface (0.15-0.30 m) soil samples were taken after the harvest of maize crop (kharif 2017&18) of maize-wheat cropping system. These samples were analysed to study the effect of Zn application at different levels (2.5, 5, 7.5, and 10 kg ha-1) and phasing of Zn (once, alternate year and every year) and one control on the distribution of Zn fractions and grain yield. The soil samples were also analysed for soil properties, available N, P, K and DTPA extractable micronutrients. Application of zinc in three phases; once, alternate year and every year along with its application at different levels had non-significant influence on soil pH, EC and OC. DTPA extractable Zn and Mn was increased with increasing Zn levels in each phase of Zn application while DTPA extractable Fe and Cu showed an irregular trend. All the fractions of Zn were noticeably higher in treatments with highest amount of added Zn at 10 kg Zn ha-1 every year than the lower doses. Among the fractions, majority of Zn was distributed in res-Zn, cryst Fe-Zn and amor Fe-Zn while rest of the fractions occupied a small portion of the total Zn present in the soil. The distribution of Zn fractions in soil was found in the order: residual Zn (Res-Zn) > crystalline iron oxide bound Zn (Cryst Fe-Zn) > amorphous iron oxide bound Zn (Amor Fe-Zn) >organically bound Zn (OM-Zn) > manganese oxide bound Zn (MnOx-Zn) > carbonate bound Zn (Carb-Zn) >specifically adsorbed Zn (SpAd-Zn)> water soluble + exchangeable Zn (WS+Ex-Zn) in both surface and sub-surface layers. Zn application to maize at 10 kg ha-1 every year had the highest grain yield which was statistically similar with Zn application at 7.5 kg ha-1 in alternate year. Hence, Zn application at 7.5 kg ha-1 in alternate year is the lowest rate at which maximum grain yield can be obtained. All the fractions of Zn exhibited positive and significant correlation amongst themselves and crop yield which indicated a dynamic equilibrium among the fractions.ThesisItem Open Access Development of spectral models for assessing soil fertility status in various agroecological sub-regions of Punjab(Punjab Agricultural University, Ludhiana, 2019) Garnaik, Saheed; Sekhon, B.S.The present study titled “Development of spectral models for assesing soil fertiity status in various agroecological sub-regions of Punjab” was carried out in five agroecological sub-regions, namely, Submountainous Siwalik Hills (SSH), Northeastern Undulating (NEU), Piedmont and Alluvial Plain (PAP), Central Alluvial Plain (CAP) and Southwestern Alluvial Plain (SWAP). The objectives were to develop visible-near infrared (vis-NIR) models for predicting soil properties and to examine portability of spectral models across regions. GPS based soi fertility maps were prepared by using inverse distance weighted (IDW) interpolation and classification. Highest soil organic carbon (SOC) and sand content (mean 0.77 % and 74.2 %, respectively) in 0-15cm soil were observed in SSH, whereas highest nitrogen, phosphorous and, manganese contents (mean value 104.5 kg ha-1, 40.8 kg ha-1, 7.8 ppm, respectively) were found in NEU. The largest potassium, copper and silt levels (mean 173.1 kg ha-1, 5.21 ppm, 22.4 %, respectively) were reported in PAP. The CAP represented highest calcium carbonate content (mean 1.36 %), while highest pH, electrical conductivity, iron and zinc (mean value 7.93, 0.95 dS/m, 29.5 ppm and 3.2 ppm, respectively) levels were observed in SWAP region. Spectral signatures in vis-NIR range were collected using ASD Spectroradiometer. Partial least square regression (PLSR) was emlpoyed to develop spectral models for assessing soil fertility attributes. Various model evaluation indices e.g. root mean square error (RMSE), ratio of performance to deviation (RPD) and coefficient of determination (R2) were used to evaluate predictive performance of the PLSR models. The RMSE, RPD and R2 values varied between 0.05 - 0.39, 0.32 – 1.73 and 0.05- 0.69, respectively in SSH for various soil properties. Similarly, in NEU RMSE, RPD and R2 values ranged between 0.05 – 0.39, 0.93 – 2.15 and 0.12 - 0.82, respectively. In PAP region, the RMSE, RPD and R2 values varied between 0.07-2.90, 0.32-1.6 and 0.05-0.72, respectively. CAP region showed RMSE, RPD and R2 values ranging between 0.03-0.43, 0.62-1.5 and 0.03-0.64, respectively. In case of SWAP region, RMSE, RPD and R2 values ranged between 0.03-0.73, 0.72-1.5 and 0.05-0.68, respectively. Moreover, in common model, RMSE, RPD and R2 values varied between 0.19-3.81, 0.16- 0.98 and 0.01-0.40. A comparison among models suggested about their non-portability across regions. Based upon various performance indices, the CaCO3 and sand predictions were reliable, whereas prediction of properties like SOC and Olsen-P was moderately reliable. The pH and EC, however, could not be predicted much accurately. The study suggested about exploring better statistical tools to enhance prediction performance of spectral models.ThesisItem Open Access Long term effect of rice straw incorporation on soil physical properties and crop productivity in rice-wheat system(Punjab Agricultural University, Ludhiana, 2019) Ramteke Pratik Rukmanand; Vashisht, B.B.The sustainability of rice-wheat cropping system in recent some years, has come into question because of multiple reasons and most recently the burning of huge amount of crop residue. From the perspective of managing surplus rice straw and an alternative to residue burning, the present study evaluated the long term (2008-2018) effect of different rates of rice straw incorporation (0, 5, 7.5 and 10 t ha-1) and nitrogen levels (0, 90, 120 and 150 Kg ha-1) on soil physico-chemical properties and crop productivity. Soil samples were analysed for different physico-chemical properties of soil and biochemical properties within soil aggregates. The study resulted that, incorporation of rice straw @ 7.5 and 10 t ha-1 along with 150 Kg N ha-1 significantly improved the soil physical properties by increasing bulk density, aggregation status, infiltration rate, soil moisture retention, and decreasing total porosity, penetration resistance and saturated hydraulic conductivity as well as increased the fertility status of soil. The biochemical properties within soil aggregates were significantly higher in macro-aggregates fraction under 10 t ha-1 rice straw incorporation rate. In simulation study with DSSAT CERES-wheat, yield, water and nitrogen balance components of wheat with changed soil properties were evaluated. Simulation study revealed that, there would be an increase in precipitation, evapotranspiration, evaporation, nitrogen leaching and decrease in uptake of nitrogen in future compared to past and present time scenarios. However, wheat grain yield would yield decline in future, which could be sustained with incorporation of rice residue over a longer period of time.ThesisItem Restricted Modelling water and nitrogen dynamics of desalinated water and fertigation in tomato under controlled conditions(Punjab Agricultural University, Ludhiana, 2019) Chawla, Ketan; Sekhon, K.S.The present research experiment was carried out to investigate the effect of two different qualities of irrigation water namely canal (CW) and desalinated (DSW) water; and three fertigation levels viz. 100% (F1), 80% (F2) and 60% (F3) of recommended NPK dose on tomato fruit yield, N uptake, water and nitrogen dynamics with HYDRUS-2D model and soil properties using drip system in a sandy loam soil under poly house conditions with four replications in a factorial randomized block design at Jodhpur Farm of PAU Regional Station Bathinda during 2017-18 in S-W region of Punjab. The results revealed that plant height increased progressively with advancement in the age of the crop under both water qualities and different fertigation levels. Both the water qualities CW and DSW produced statistically similar plant height, number of fruits per plant, average fruit weight, total dry matter production and total fruit yield of tomato. However, the increasing fertigation level from 60% of recommended NPK dose (F3) to 100% (F1) of recommended NPK dose significantly increased the plant height, yield components, total dry matter and fruit yield of tomato at successive growth stages. The N content of different partitioned plant parts viz. leaves, stem and roots decreased with each successive growth stage, irrespective of water quality and fertigation levels. Water quality had no significant on the N content and uptake of leaves, stem and roots at successive growth stages (120 DAT, 150 DAT, 180 DAT and at maturity). Highest fertigation rate (F1) recorded highest content and accumulation of N in leaves, stem and roots while lowest under F3 at all growth stages. The absorption of N by tomato leaves increased with increasing plant age upto 150 DAT whereas the total N accumulation tended to decline at 180 DAT and maturity at all the fertigation rates in both the water qualities. Unlike tomato leaves, the total N removal in stem and roots continued to increase at successive stages of tomato growth upto maturity. The N content in fruits produced with both water qualities was also statistically similar but the fertigation levels had a significant effect on the N content of fruits at 7th picking and final harvest. The effect of water quality and fertigation levels on the pH, electrical conductivity, organic carbon content and SAR of the soil was found to be non-significant at all the soil depths (0-15, 15-30, 30-45 and 45-60 cm). Irrigation water quality didn’t influence the available N, NH4 +-N and NO3 --N content of the soil but fertigation levels significantly influenced all these forms of N in soil at all the depths except for NH4 +-N and NO3 --N in 45-60 cm soil depth. The maximum available N, P and K content of the soil was recorded under F1 followed by F2 and minimum in F3. The influence of water quality and fertigation levels on sodium adsorption ratio (SAR) and bulk density of soil was found to be non-significant in all the depths signifying the analogous effect of desalinated (DSW) water on soil properties as that of canal water (CW). The comparison between the observed and predicted values of water and nitrogen content in a sandy loam soil for both calibration and simulation of HYRUS-2D had high value of R2, low value of RMSE, and high index of agreement which showed that model was predicting the water and nitrogen content values with greater accuracy in tomato crop under protected cultivation. These results indicated the similar effect of canal water (CW) and desalinated water (DSW) on fruit yield of tomato and soil properties with drip system. It suggests that desalinated irrigation water quality comparable to canal water along with 100% fertigation under drip can be used successfully for growing of tomato on sandy loam soil under controlled environment during the initial years of its cultivation.ThesisItem Open Access Sorption and desorption behaviour of chromium (VI) in soils(Punjab Agricultural University, Ludhiana, 2019) Satnam Kaur; Dhanwinder SinghSorption and desorption of chromium (VI) were examined on twenty eight surface and subsurface soil samples collected from four different locations viz Ludhiana, Jalandhar, Malerkotla and Mandi Gobindgarh. Sorption of Cr was carried in presence of background electrolyte 0.01 M Ca(NO3)2 solution. Sorbed Cr was desorbed back by resuspending the same soil samples in fresh Cr-free 0.01 M Ca(NO3)2 and giving five repeated washings sequentially. Chromium sorption was observed to be significantly and negatively correlated with pH both in surface (r = -0.764) and sub-surface samples (r = -0.757). Simple linear regression model for different soil variables showed that 58% and 57% of the variation in Cr sorption in the surface and sub-surface soils under study, respectively, was explained by soil pH. The stepwise multiple regression model showed that other factors, like total Cr and EC could marginally increase the variability to 68% in surface soils and OC to 61% in subsurface soils. The amounts and patterns of chromium desorbed varied among the soils. Chromium desorption was significantly and positively correlated with soil pH both in surface (r = 0.635) and sub-surface (r = 0.438) soil samples. Among polluted samples, 51% variability was explained by pH in surface samples and 80% variability in sub-surface samples by pH, EC and clay content. In non-polluted soils, CEC, CaCO3, DTPA extractable Cr and total Cr together explained 91% variability in Cr desorption in surface samples and OC, CEC and DTPA extractable Cr explained 66% variation in sub-surface samples. The Cr sorption data of the three selected soil samples were very well described by Langmuir adsorption isotherm (R2=0.959 to 0.994), Freundlich adsorption isotherms (R2= 0.985 to 0.994) and Dubinin–Radushkevich (D-R) adsorption isotherm (R2=0.926 to 0.973). The Cr desorption data of the soils well fitted to Langmuir desorption isotherm (R2= 0.967 to 0.992). Effect of pH on Cr sorption-desorption was also studied by adjusting the pH of each of three selected surface soil samples in the range of 6-8 in the laboratory. The sorption of chromium decreased with the increase in soil pH from 6 to 8. Chromium sorption data fitted well in Langmuir (R2= 0.924 to 0.995), Freundlich (R2= 0.977 to 0.995) and (D-R) (R2= 0.954 to 0.981) adsorption isotherm equations at all pH levels. Percent chromium desorbed increased with the increase in pH from 6 to 8.